The CAT1232LP and CAT1832 microprocessor supervisors can halt and restart a “hung-up” or “stalled” microprocessor, restart a microprocessor after a power failure, and debounce a manual/push-button microprocessor reset switch.
The devices are drop in replacements for the Maxim/Dallas Semiconductor DS1232LP and DS1832 supervisors Precision reference and comparator circuits monitor the 5V or 3.3V system power supply voltage, VCC.
During power-up or when the power supply falls outside selectable tolerance limits, both the RESET and RESET¯¯¯¯¯¯ become active.
After the power supply voltage rises above the RESET threshold voltage, the reset signals remain active for a minimum of 250ms, allowing the power supply and system processor to stabilize.
The trip-point tolerance input, TOL, selects the trip level tolerance to be either 5% or 10% for the CAT1232LP 5V supply and 10% or 20% for the CAT1832 3.3V supply.
Each device has a push-pull, active HIGH reset output.
The CAT1232LP also has an open drain, active LOW reset output while the CAT1832 also has a push-pull, active LOW reset output.
A debounced manual reset input activates the reset outputs and holds them active for a minimum period of 250ms after being released.
Also included is a watchdog timer to reset a microprocessor that has stopped due to a software or hardware failure.
Three watchdog time-out periods are selectable: 150ms, 600ms and 1.2s. If the ST¯¯ input is not strobed low before the watchdog time out period expires, the reset signals become active for a minimum of 250ms.

* Selectable reset voltage tolerance
- CAT1232LP for 5V supply
- CAT1832 for 3.3V supply
* Selectable watchdog period: 150ms, 600ms or 1.2s
* Two reset outputs
- Active high, push-pull reset output
- Active low, open-drain reset output (CAT1232LP)
- Active low, push-pull reset output (CAT1832)
* Debounced manual push-button reset
* Compact SOIC and MSOP packages

* Microprocessor Systems
* Portable Equipment
* Controllers
* Single Board Computers
* Instrumentations
* Telecommunications


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